The anode port usually has either an anode rod or a plug in it. The only explanation for what you describe is that someone needed a place to connect a hot water pipe and that was the easiest spot. WHERE it goes, howver, we cannot even begin to tell you that.

Removing the (sacraficial) anode from a WH could significantly shorten its service life. Depends some on your water quality. The anode gets preferentially eaten away rather than the steel lining of the tank. Remove it, and you are totally at the mercy of the quality of the liner. WIth it, even with a small defect in the liner, the anode gets eaten up rather than the tank. If you keep a good anode in the tank, it can last a very long time.

Jim is right, and removing the anode could void warranty on your new tank as well as shorten its life. Why not just cut a valve into the line and turn it off, then go around and see where there is no more hot water. Then you will be able to plumb it up right when you put in the new tank.

The anode is a 3/4" pipe tap. By the time the original anode has deteriorated, ALL exposed metal surfaces should already be coated with the anode's material. What do you mean by " hook it up tne same way"? Does that mean you will REMOVE the anode rod. That is NOT a good idea on a new water heater. There is no warranty issue with removing the anode rod, because when a heater fails under warranty, NOBODY looks at it. It goes directly into the scrap pile.

Maybe I'm all wet, but my understanding of a sacraficial anode is that because it is more reactive than the steel (iron) in the tank, it gets eaten away rather than the steel (iron). It ends up as ions and stays in suspension and is flushed out with the water as used. As opposed to a closed system like in a boiler, there is constantly new, reactive, air carying water being replaced in the tank, so it is an on-going battle to decide which part gets eaten up. So, like on bouys, ships, bridge abutments, and anything else that may be in water, keeping the anodes replaced and intact helps extend the life of the thing they are attached to. With anything, though, it is a losing battle, and eventually, while the corrosion is mostly controlled by the sacraficial action, some occurs elsewhere (in the tank), so it can't stop it forever. But, you can slow it down considerably if you keep a full anode in there. On a ship, and other big expensive items, they repaint them periodically...can't do that to the inside of your WH tank, but those ships, etc. would be a rusting hulk much sooner if they didn't have and replenish when required, their sacraficial anodes.

ok so i installed the tank yesterday and traced back the 1/2 line coming out of the anode port.

the guy had ran 1/2" out of the anode port then into the crawl space where he Tees off and runs 1/2" line down around 25 feet to a bathroom and then ties back into the 3/4" right before it goes upto the fixture.

the other side runs to the kitchen and then ties in the same.

has anyone heard of this before? im guessing its maybe a trick to gain more water pressure?

i have seen many suspect plumbing work in the house. Ie. bent nails as hangers touching the copper.